This application for a NIDA Development R34 grant responds to PA-10-013 to develop an integrated treatment for comorbid post-traumatic stress disorder (PTSD) and substance abuse (SA) in adolescents. The study aims to develop a treatment approach that is community-friendly and deliverable by substance abuse counselors (SAC) in outpatient settings. The proposed Trauma-Focused Substance Abuse Treatment (TFSAT) aims to reduce PTSD symptoms and substance use and to build coping skills. This is a Stage I application which proposes to adapt an evidenced-based trauma program, Cognitive-Behavioral Intervention for Trauma in Schools (CBITS), for adolescent substance abusers (ASAbusers); to integrate CBITS with evidence-based cognitive behavioral therapy for adolescent substance abuse; to assess the acceptability and feasibility of the integrated approach; and to pilot test the new program against standard care. ASAbusers experience a wide range of traumatic events and PTSD is prevalent (30% to 47%) in this population. ASAbusers with PTSD are often not identified and drop out of treatment or relapse early. Given this high prevalence of trauma exposure, it is crucial to increase PTSD treatment accessibility and implementation in AOD treatment facilities. Thus, we propose to train SAC to deliver an integrated PTSD-SA treatment, taking advantage of the cognitive-behavioral orientation of both PTSD and SA treatments, the cost- effectiveness of utilizing SAC for integrated treatment, and the potential for dissemination of a new paradigm within existing treatment centers. The proposed study uses both qualitative and quantitative methods to develop and evaluate the integrated treatment. Expert panels and focus groups with multiple clinical and community stakeholders will be convened to refine the program. A controlled pilot study of the intervention will be conducted with 50 ASAbusers assigned to either TSFAT or standard care. Primary outcome measures will include assessments of the acceptability and feasibility of the treatment protocol and changes in PTSD symptomatology and substance usage pre- and post-treatment. The goal is to develop a community-friendly treatment that can be delivered in real-world settings. PUBLIC HEALTH RELEVANCE: Trauma exposure and post-traumatic stress disorder (PTSD) are highly prevalent in adolescent substance abusers and are associated with early relapse and treatment dropout. In outpatient treatment facilities for adolescent substance abuse, access to PTSD treatment is limited and current clinical practice paradigms are disjointed and ineffective. This is the first study to develop an integrated treatment approach for comorbid PTSD and substance abuse that is community-friendly and deliverable by substance abuse counselors in outpatient settings.